I'm trying to write a test that checks for data overruns using VirtualAlloc and VirtualProtect and I think I may have found a bug. Here is the problem:
DWORD dwPageSize; BYTE * twoPages, temp; DWORD flOldProtect; twoPages = VirtualAlloc(NULL, 2 * dwPageSize, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE); res = VirtualProtect(twoPages + dwPageSize, dwPageSize, PAGE_NOACCESS, &flOldProtect); temp = twoPages[dwPageSize + 1]; // should cause exception but doesn't in wine twoPages[dwPageSize + 1] = 0; // does cause exception
Say, that code fragment wasn't complete, was it? Looks like dwPageSize was uninitialized...
I would like to write a test to check the exception handling but I don't know how to do a __try and __except in C.
OK, I don't know much about it either. A little googling shows: http://www.kerneltraffic.org/wine/wn20030516_170.html#8 makes it sound like __try is hard to do with gcc. You might need to punt and, when compiling with gcc, do nothing unless building in winelib, where you'd set up a handler for SIGSEGV to catch the bad access. http://www.codeproject.com/cpp/transactions.asp?df=100&forumid=11253&... has some examples of how __try is used in visual C. (Note that you can download a copy of visual C's commandline compiler free from Microsoft.)
What confuses me is, doesn't MinGW support __try? Hrm. - Dan
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Dan Kegel